HF Propagation: Variation of the Frequency

In the following post I show some visual results of my Voacap simulations. The visualization has been done using some python and shell scripting.

Simulation Parameters

  • Antenna: isotrope

  • Mode: cw (required SNR for circuit reliability calculation: 24 dB)

  • Power: 50W

  • Transmitter location: JO40DA

  • Month: July

  • SSN:72.8

  • Time (UTC): 12h (=day) and 23h (=night)


Night Time - HF Propagates Nicely


SNR (dB)


Circuit Reliability (%)

Day - We have Damping


SNR (dB)


Circuit Reliability (%)